The story of Jimmy Hoffa is a tangled tale with tentacles that stretch from Cuba toNortheast Pennsylvania, Detroit to Las Vegas.His disappearance is one of the most famous missing-persons cases in history.New light is shed on the old mystery in an episode of “History Detectives Special Investigations,” “Who Killed Jimmy Hoffa?” scheduled to air Tuesday, July 22, at 9 p.m. on PBS affiliates, including Northeast Pennsylvania’s WVIA.Mr. Hoffa, the former head of the Teamsters union, vanished on July 30, 1975. No trace of him has ever come to light.The History Detectives’ investigation focuses on who killed Mr. Hoffa and why.The who is most likely hitman Frank Sheeran, who did so at the direction of Kingston-based mafia boss Russell Bufalino, according to some experts.But why?Mr. Hoffa knew too much. And he was starting to talk about it, the experts say.Matt Birkbeck, author of the Bufalino story “The Quiet Don,” is a former reporter for the Morning Call in Allentown and author of four other books. He is an award-winning investigative journalist who currently covers Wall Street for Harrison Scott Publications and lives outside of Stroudsburg.Mr. Birkbeck said he was contacted by History Detectives Special Investigations last May when they first found out about “The Quiet Don.”“Apparently they had been working on this. They saw the book, and one of the producers reached out to me,” he said.Mr. Birkbeck said he met with the investigators and was “on board with what they were doing,” particularly on the research side.“They were very, very big on backing everything up,” he said. That is something he, as a journalist, looks for.Last summer, History Detectives investigator Kaiama Glover interviewed Mr. Birkbeck at the Villa Foglia restaurant in Exeter for the Hoffa episode of the show.Mr. Birkbeck said Mr. Bufalino used to hang out at the restaurant and knew the owner, Bernie Foglia, who allowed its use for taping the show.Mt. Birkbeck said he just previewed the show himself.“They were great. I thought they did a wonderful job,” he said.The investigators cover a lot of ground, from the restaurant in Detroit where Mr. Hoffa was last seen to Las Vegas, where the Teamsters’ pension fund was a “virtual piggy bank” for the mafia.History Detectives investigator Tukufu Zuberi went to Philadelphia to interview Charles Brandt, author of “I Heard You Paint Houses,” which tells the story of Mr. Sheeran, a close associate of Mr. Bufalino and a friend of Mr. Hoffa.Mr. Brandt’s book reveals that Mr. Bufalino ordered the hit on Mr. Hoffa, and Mr. Sheeran carried it out.The investigation of Mr. Hoffa’s disappearance had, at one time, more than 200 FBI agents involved, Mr. Birkbeck said. They had an idea of who was involved in it, but couldn’t get enough evidence to bring anyone to trial, he said.For the show, Ms. Glover dug up recently declassified government files on Mr. Hoffa, including a memo indicating the FBI suspected the mafia was responsible for his disappearance but couldn’t prove it.Mr. Birkbeck said it takes the Hoffa story to a whole other level by introducing the Bufalino element, and how he gave in to the mob’s wanting Mr. Hoffa — a friend of Mr. Bufalino’s — dead.In the History Detectives episode, investigator Wes Cowan shares recordings made by President Richard Nixon — who had his own office bugged and recorded everyone who came in — talking about Mr. Hoffa.Mr. Birkbeck said he was familiar with most of the material in the program, except for the Nixon tapes, which he would have put in his book if he had known about them.“I thought that was awesome,” he said. “It was a really good ‘get’ on their part.”Contact the writer:eskrapits@citizensvoice.com